On Thu, Dec 31, 2020 at 11:37 AM Theodore Ts'o <tytso@mit.edu> wrote:
Twenty years ago, one of larger customers for the company I was
working for at the time (VA Linux Systems) was one of the new
electronic stock exchanges, and they were using Linux boxes with
PDP-11 emulators because their stock trading software was written in
Macro-11 and running on RSTS/E.  They had tried three times to rewrite
it so it could run on something more modern, but each time, the
rewrite had ended in failure.  So they simply sharded the problem, so
one x86 server running RSTS/E in emulation would service stocks
symbols AAAA--ADZZ, and the next would service stocks AEAA--AFZZ, and
so on.  Given that this was back in 1999, I assume they had solved the
Y2K problem one way or another, but even if they hadn't yet, I suspect
it would have been easier for them to fix the problem by asking their
dedicated Macro-11 Software Engineering team to fix it, than to ask
that same team to help the other team put themselves out of a job
(which for some reason, never seemed to happen successfully...)

This is the sort of reason why QBUS x86 machines exist...  Not cheap, or easy to come by these days, but they filled a niche of emulation but with access to real hardware... Nor easy to find with a web search, it seems :(.

There's a number of nuclear power plants that employ MACRO-11 programmers because they can't swap out the old gear w/o going through a prohibitively expensive recertification process... It's cheaper to hire and train good programmers than it is to go through that process :(.

Warner